Kim Jong-Nam's murder is re-enacted at Kuala Lumpur airport

Two more suspects have been arrested in connection with the death of Kim Jong-nam, the brother of North Korean leader Kim Jong-un, in Malaysia.

They were identified as Siti Aisyah, 25, an Indonesian citizen, and a Malaysian man who was believed to be her boyfriend.

That led to the arrest of the two women, one carrying a Vietnamese passport and the other with an Indonesian one.

Police also detained a Malaysian man to assist in their inquiries, and are still hunting for four men they believe were involved in the murder.

According to the South Korean intelligence agency, the North Korean spy agency had received a standing order to assassinate Kim Jong Nam five years ago, when Kim Jong Un became the supreme leader.

As a consensus grows that the country's political leaders ordered Mr. Kim's death, multiple theories are emerging for why they singled him out, and why now.

There is widespread speculation that North Korea was behind the killing, but there has been no proof.

There are reports that Malaysian officials have refused efforts by North Korean officials to stop a medical exam of the body.

Jong Un's estranged half-brother Kim Jong Nam, 46, was at the airport on Monday to catch a flight home to Macau when he was sprayed with a form of liquid and had his face swabbed with a piece of cloth.

But Kim Chang-su at the Korean Institute for Defense Analyses tells Elise that Kim Jong Un may have perceived his brother as a threat: "He's on the throne".

The Japanese journalist did not try to speculate on who might be behind Kim Jong-nam's killed at Kuala Lumpur International Airport or if it was tied to North Korea.

Kim Jong-nam was widely considered the heir apparent of his father several years ago, and it remains uncertain what precisely caused his fall from grace.

Even though Kim lived with his family in Macau, his body will be sent to North Korea at the request of the government in Pyongyang, the capital of North Korea, the Malaysian news media said.

One Chinese journalist who spoke to the Asahi on the condition of anonymity said Beijing is concerned about public opinion, which is heavily leaning toward North Korea abandonment.

While this will most likely come from one of his children - Kim Jong Nam is thought to have six of them - it introduces another wrinkle in a sensational killing that makes a James Bond plot look realistic.

The late leader was also the father of Kim Jong-nam.

The Kim family dynasty has ruled North Korea for three generations since its founding after World War II.

On Feb. 15, the same website described reports about the murder of Kim Jong-nam from newspapers in various countries as being "unconfirmed" and concluded that "some kind of plot or conspiracy is taking place".

Even more damaging, Kyunghyang Shinmun's report quoted anonymous sources to report that Kim Jong-nam had attempted to defect to South Korea, the United States, and Europe - news that could seriously weaken the Kim dynasty's stature in the eyes of North Korea's elites and commoners.